Improvement in tubular boilers



UNITED STATES PATENT CEEICE.

CHARLES HAYV'IHORN, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN TUBULAR BOILERS.

Specification forming part of Letters Patent No. 45,494, dated December 20, 186i.

To all whom it may concern:

Beit known that I, CHARLES HnwrHoRN, of the city of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Tubular Boilers and I do hereby declarel the following to be a full, clear, and exact description thereof, reference beingha-d to the accompanyin g drawings, forming part ofthis speciiication, which represent a side view of two iiues in a tubular boiler with a portion of the boiler-head, one of the iiues being shown in section.

The object of my invention is to prevent the loosening' of the tubes or tlues in the boilerheads caused by the alternate heating and cooling ot' the boiler, which allows the escape ot' water and steam; and my invention consists in the improved mode hereinafter described nor is any shoulder formed upon it, but it is inserted into the guttered hole, the diameter of the flue corresponding with the smallest diameter of the hole, which is on the inner surface of the boiler-head. rIhe diameter of the hole on the outer surface of the boilerhead may be somewhat larger than on the inner surface, or it may be the same; but the diameter ofthe hole midway `between the two surfaces of the boiler-head plate is greater. The extremity of the Hue is protruded through of fastening the ends of the tubes or ilues in l the hole suiiiciently to allow the end of the the boiler-head.

tlue to be upset as at e around the hole against The mode ot' attaching the extremities of the outside of the boiler-head in the usual lines to the boiler-head of tubular boilers now ordinarily practiced is to make the hole in the boiler-head into which the extremity of the iiue is inserted ot' smaller diameter than that part ot' the flue which traverses the interior of the boiler, and to reduce correspondingly the uid ot' the ilue which is to pass through the hole, so as to make on the flue a shoulder which will rest against the inside ofthe bollerhead around the hole. The projecting extremity of the flue is then turned down and llammered around the hole on the outside of the boiler-head, which has the eifect ot' drawing the shoulder ou the iiue close up to the inside of the boiler-head around the hole. This makes a very close and tight joint around the iiue so long as the boiler remains cold, but when it is heated the expansion of the boiler head and nue and its subsequent cooling frequently repeated gradually loosen the tine, and a leak at the joint is theinevitable consequence.

In the drawing, a is the tine-head of the boiler, and b c are two fines inserted and attached in the manner which I have invented. lhe circular hole in the boiler-head designed to receive the flue is made in the first instance cylindical, and of the same diameter at the inner surface of the boiler as the ilue to be inserted. In the face of the iiue-hole a gutter, d,

is then cut by a proper tool, the gutter being either curved or V-shaped, as may be preferred, and extending all around the circular hole. The gutter may either extend from manner. bridges the gutter in the hole in the boilerhead is then forced down into the gutter by means ot' expanding dies or other suitable tools until the flue is driven down into the gutter all around the-hole inthe manner shown in the drawings.

The advantages which I claim for my invention are great simplicity of construction, freedom from liability to loosen at the point of union between the ilue and boiler head, and increased strength of boiler, owing to the addition-al hold which the enlarging of the diameter of the flue within the hr le in the boilerhead gives to the flue, so that each flue serves more strongly to brace the boiler.

What I claim as my invent-ion in the const:uction of tubular boilers is- Making the holes in the heads of tubular boilers for the insertion of the Ilues with a gutter in the wall or sides of the nue-hole, and forcing the sides of that part oi' the flue which passes through the hole down into the gutter, so as to make the flue conform to the shape of the hole, substantially as and for the purposes hereinbefore described.

In testimony whereof, the said CHARLES IIAWTHORN has hereunto set his hand in presence of us.

CHARLES IIAWTIICRN.

Witnesses A. S. NICHOLSON, J. M. NEAL.

That portion of the flue which 

